Cons: much more likely to delaminate from structural stresses....It also requires vacuum bagging if done correctly. The vacuum process can then give the painted surface a honeycomb pattern on a warm day. Very few molding manufacturers use honeycomb in their layups and those that might have at one point often switch to core materials such as rohacell or balsa if required. The use of honeycomb for formers is more common however.

I think Billy meant to say sandwich construction, at least that was what he told me when we talked at Ejets about the changes JTM where gonna make to their production. That would be Rohacell/balsa/Airex or similar as core material the same way as most other manufacturers do it, of course it still needs to be vacuum bagged.